The invention relates generally to medicament applicators, and in particular, to an actuator used to actuate a container for the administration of a medication or other substance to the nasal cavities and/or lungs of a user.
The nose can be an important route for the delivery of various substances aimed at treating various ailments, including various upper respiratory ailments such as rhinitis and sinusitis. Most of the substances delivered to a user through their nose, and in particular to the user""s nasal membranes, are delivered in aerosol or aqueous form through nasal medicament applicators, including pressurized metered dose nasal inhalers, nasal sprayers, and dry powder inhalers. For example, nasal sprayers transform a liquid substance into airborne particles for application to the nasal cavity. Such a device generally includes a container filled with a liquid substance and having an actuator portion.
One of the more significant problems with nasal sprayers is nasal drip and oral ingestion of the substance. These problems are caused by airborne particles that are too large to be absorbed by the targeted nasal area (i.e. the nasal turbinates). Rather than reaching, or being absorbed by, the target area in the nasal cavity, these particles tend to fall back out of the nose or make their way to the back of the throat and eventually into the stomach. The problem is further compounded by the fact that the larger particles comprise the most medication, thus resulting in wastage of medication. In addition, another problem with such devices is that at the end of an application, there may be a few large droplets of medication barely clearing the tip of a nozzle, or other member adapted to be inserted into the nose of the user. Typically, such large droplets are caused by the diminishing energy levels experienced at the end of the flow burst, which results from the physics involved during the application.
Typically, nasal sprayers are held with the index and middle finger positioned on opposite sides of a nosepiece, or nozzle, and the user""s thumb positioned under the container that holds the medication. Similarly, pressurized metered dose inhalers are typically actuated by holding an actuator boot with the user""s thumb and thereafter pushing on the container. Often, in order to place the nosepiece properly in the nostril, or a mouthpiece in the mouth, the hand and wrist are bent or arranged in an awkward position, which can result in discomfort to the user, and/or misalignment of the nozzle with the nasal membranes, with an attendant misalignment of the medication plume. In addition, users often do not actuate the device with a firm, brisk motion, which can result in poor aerosolization of the medication. In addition, the actuation may tend to move the nozzle away from the target area in the nose. Such uncoordinated and/or weak actuation can result in wasted medication and inadequate treatment.
Nasal applicators also typically are not provided with an indicator mechanism that would indicate the number of doses of medicament or substance that have been dispensed from or remain in the container of medicament. Therefore, such applicators typically do not alert a user that the container should be refilled or replaced.
Briefly stated, in one aspect, various preferred embodiments of applicators are aimed at addressing one or more problems associated with devices used to deliver a substance, preferably a medicament, to the nose or mouth. In one embodiment, a nasal applicator includes an actuator comprising a nozzle with an end having a first outlet and a diffuser comprising a first portion and a second portion. The first portion is disposed on the nozzle and the second portion forms a passageway communicating with the first outlet. The second portion has a second outlet communicating with the passageway. The second outlet is spaced from the first outlet. Preferably, the passageway is tapered. In a preferred embodiment, the first portion comprises an inlet, which communicates with the passageway, located adjacent the first outlet.
In one preferred embodiment, the nozzle and diffuser are integrally molded. In such an embodiment, the diffuser, otherwise referred to as a nozzle, includes a passageway having a tapered portion.
A method for dispensing a substance into a nasal cavity of a user comprises inserting an end of the diffuser into the nasal cavity, dispensing the substance from the applicator into the passageway and dispensing the substance from the passageway through the second outlet into the nasal cavity. In one preferred embodiment, the user further inhales air through the inlet and into the passageway.
In another aspect, an actuator is used to dispense a medicament from a container having at least a first and second portion. The actuator comprises a holder that is adapted to engage at least the first portion of the container and a trigger member moveably connected to the holder. The trigger member is moveable between at least a first trigger position and a second trigger position. A push member is coupled to the trigger member and is moveably connected to the holder. The push member is moveable between at least a first pusher position and a second pusher position as the trigger member is moved between the first and second trigger positions. The push member is adapted to move at least the second portion of the container relative to the holder as the push member is moved from the first pusher position to the second pusher position.
In one preferred embodiment, the trigger member is pivotally connected to the holder and the push member is hingedly connected to the trigger member. In one preferred embodiment, the push member comprises a first and second push member. In another preferred embodiment, the trigger member comprises a first and second trigger member.
In another preferred embodiment, a trigger member is pivotally connected to a holder at a pivot axis. The trigger member is pivotable about the pivot axis in a first direction toward a grippable portion and a second direction opposite the first direction. A push member is connected to the trigger member and is pivotable about the pivot axis in the first direction as the trigger member is pivoted in the first direction. The push member is pivotable about the pivot axis in the second direction as the trigger member is pivoted in the second direction. The push member is adapted to move at least the second portion of the container relative to the holder as the push member is pivoted in the first direction.
In one preferred embodiment, the push member includes an engagement portion adapted to engage the container. In one preferred embodiment, the actuator includes a stop member moveable between an engaged position, wherein the stop member is engaged with at least one of the push member and the container and immobilizes the engagement portion, and a disengaged position. In one preferred embodiment, a trip member is coupled to one of the push member and is moveable between at least an engaged position, wherein the trip member is engaged with the stop member after the trigger member has moved along a predetermined portion of a path of travel as it moves in the first direction, and a disengaged position. The trip member disengages the stop member from the push member when the trip member is moved to the engaged position.
In another aspect, the actuator includes an indicator mechanism. The indicator mechanism includes an indicator member that is rotatably mounted to the holder and a drive mechanism connected between the indicator member and at least one of the trigger member and the push member. Preferably, a predetermined number of movements of at least one of the trigger member and the push member in at least one of the first and second directions causes the drive mechanism to move the indicator member an incremental amount. In one preferred embodiment, the predetermined number of movements is one. Also in one preferred embodiment, the drive mechanism includes a pawl engaging a ratchet gear and a worm coaxially mounted with the ratchet wheel. The worm meshes with and moves the indicator member.
In another aspect, a method for dispensing a medicament from a container comprises engaging at least a first portion of a container with a holder, moving a trigger member relative to the holder between at least a first trigger position and a second trigger position, moving a push member with the trigger member between at least a first pusher position and a second pusher position as the trigger member is moved between at least the first and second trigger positions, engaging at least a second portion of the container with the push member, and moving the second portion of the container relative to the holder with the push member as the push member moves between at least the first and second pusher positions.
In another preferred embodiment, the method includes engaging at least the first portion of the container with the holder, pivoting the trigger member about the pivot axis in a first direction, pivoting the push member about the pivot axis in the first direction and engaging at least the second portion of the container with the push member. The method further includes moving the second portion of the container relative to the holder and the first portion of the container with the push member as the push member pivots about the pivot axis in the first direction. In one preferred embodiment, the method further includes engaging one of the container and push member with a stop member and thereby immobilizing the engagement portion of the push member as the trigger member is pivoted in the first direction along at least a portion of a path of the movement of the trigger member. Preferably, the method further comprises engaging the stop member with a trip member and disengaging the stop member from one of the push member and the container, and thereafter moving the second portion of the container with the push member.
In one preferred embodiment, the method further includes indicating the number of doses remaining in or dispensed from the container. In yet another aspect, various methods for assembling an actuator are provided.
The presently preferred embodiments provide significant advantages over other medicament applicators, including various nasal sprayers. In particular, the applicator creates a better particle size distribution to increase the proportion of particles reaching and being absorbed by the targeted nasal area. By achieving this objective, nasal drip and oral ingestion will be reduced. In particular, the applicator reduces the amount of large aerosol particles leaving the nasal sprayer as well as slowing down the aerosol as it leaves the nasal sprayer. This reduction of speed allows the remaining aerosol particle to land on the interior turbinate and the nasal floor where benefits of the medication can be maximized.
The presently preferred embodiments of the actuators also provide significant advantages. In particular, the configuration of the trigger member and push member conforms to the natural position of the user""s hand, and allows for better positioning of the fingers and thumb. In addition, actuation is effected simply by squeezing of the trigger member, which results in a more brisk, upward motion of the container and a better aerosolization of the medicament. Moreover, the squeezing of the trigger member is preferably performed laterally relative to the movement of the container, and does not tend to move the nozzle relative to the target area. The various holder, trigger member and push member can be assembled by snap-fit, which reduces the part count and simplifies the manufacturing process. In addition, the actuator has an appealing aesthetic appearance, with various surfaces that can be decorated with various information, including source and medication identifiers.
The stop member also provides significant advantages. In particular, the stop member allows the trigger member to temporarily store energy in a spring acting on the engagement portion of the push member. In various preferred embodiments, the spring is disposed between the trigger member and the push member, or between various components of the push member. When a predetermined, desired amount of potential energy is stored or accumulated in the spring, the stop member is dislodged, for example by a trip member, such that the energy can be released or dissipated from the spring as it acts upon the container via the push member. In this way, a consistent, repeatable actuation force is applied to the container, with the actuation avoiding various dispensing problems associated with uncoordinated or weak actuation of the container and actuator. As such, the actuator enhances and provides more consistent treatment while avoiding wasted medication.
The indicator mechanism also provides significant advantages. In particular, the indicator member indicates to the user that the container should be replaced. In this way, the user can plan ahead in obtaining refills or new containers.
The foregoing paragraphs have been provided by way of general introduction, and are not intended to limit the scope of the following claims. The present invention, together with further objects and advantages, will be best understood by reference to the following detailed description taken in conjunction with the accompanying drawings.